High-potential-measuring instrument.



No( 850,065; l PATNNTND APR. 9, 1901.

H. SHOBNIAIITII.

HIGH POTENTIAL MEASUNING INSTRUMENT.

APPLICATION FILED 00T.29.1906.`

strain the amount'ot discharge through the tube A when the instrument is used in connection Withfcircuits et exceptinnatl;Y high potentials. lf the potential to be measured is thatof a perfectly continuous current-- that is, not in the form of impulses, oscilla t-ions, or alternations-the condensers H lf are preferably supplanted by extrenndy hij-h resistanees.

A second scale S', having graduations g", is provided for a case Where one or both ol' the condensers are omitted. In other words, the instrument is a double-scale instrument, one scalebeing used tor one range ot' potentials, the. other scale beingr used for another range of potentials. By dill'erent values ol' the eapaeity of either of the eondensers K l ditferent calibrations are obtained and` dillerent ranges given to the instrument.

The distance between the. terminals l l and the nature and pressure of the gas are preferably so chosen that a direct spark discharge doesnot take. plaee. lt is preferred thatthe. invisible discharge or a brush dis charge onl7 be permitted. lith the volumes ot the right and left hand systems very great as compared to the volume ot the thermometer-tube the instruriient will give dei'leetions proportionate. to the potentials, and the arrangement here shown requires no correction for temperature changes ot the surrounding atmosphere, particularli7 when the volumes of the two systems to the right and left of the seal c are equal or very nearly equal.

In Fig. 3 the ammeter arrangement is shown. The terminals il and ll are sealed into the ends ol the tube l) of relatively laure bore and are connected by a (Yerman-silver or other Wire ll ol, say, No. 4t) ll. and S. ,faire lor small currents. llere the heat developed in the wire lll by the passage of thegeurrent to be me: sured causes an expansion similar to the expansion caused in the Voltmeter in Figs. l and IZ by the discharge. ln other respeets the instrument is similar to the volt.- meter.

lt is to be understood that l do not routine myinvention tothe form of apparatus here illustrated, lor other dispositions ol' the va rinus parts may be adopted without.- varyingr the principle or the results, and sis/.es et terminals lJ and Pand oll wire lll may be 2.- ln au electrical measuring instrument.,

stance a tube et relatively small bore, a seal ad apted to move therein, a chamber communicatiin with said tube, and cireuit-terminals se rated trom each other within said chamber and adapted to have n dist ntrge passed bctween them.

3. ln an electrical measuring instrument,

the combination with a. tube having 'a small bore, of a seal adapted to move therein, a. chamber communicating' with said tube, and electrical tern'iinalsseparated "from each other in said chamber and connected by a gas or vapor path. I

4f In an electrical measuring` instrument, the combination withv chambers of praetically equal volumes,` of' a tube ot relatively small bore comiecting the same, a. seal adapted to move in said tube eirei:it-terA i'ninals in one oi said chain-bers, and a or vapor path bridging said ter iinals.

5. ln an electrical measuririfc, instrument, the combination with chambers of practically equal volumes, a tube of relatively small bore connecting said chambers, a seal adapted to move in said tube, one ot' said vchambers com rising communicating bulbs,

circuit-termina disposed in said bullas, and a gas or vapor path 'ridgung` sind terminals.

6. in an electricalmeasuring instrument, e

the combination with a tube ofsniall bore, of a seal movable therein, a. chamber having separated circuit-terminals, a gas or virer bridging said terminals for absorbing; e ec' trical energy to produce heat, and 4a ground# i glass connection between said chamber and tube.

`7. In an. electrical measuring instrument, a. tube of relatively` small bore, a seal mov;

' able therein, a chamber communicatingwith said tube, a. second chamber communicating with said tube, separated electrical terminale in said second chamber, means bridging said terminals to absorb electrical ener-53 and etarent-restraining means external. Ato said chamber and in circuit ,with said terminals.

8. ln an electrical measuring instrument,

a tube of relatively small here, a seal mov.- able therein, a chamber communmailling`v with said tube, a second chamber communi"` eating with said tube,- separated electrical terminals in said second chamber, means,

IOt

IIC

a glass u0nnectjng-tub of small bore, gggm-lfallxwl my signature in the presem'o of the able seal in saidUQQnecting-tube, one osaid Vtw@ subscribing wtnvsses. clml-'nbers boing detlmblg from saidk tube, sepan-ated electrical terml's' in said A@11m11- 5 .ber,-,nnd n. gas or vapor path bridging said Witnesses: terminals. ELIZABETH DUFFY, 11.1.testin1u11y whereof l yhave hereunto l JAMES M. SAWYER.

HARRY suman-nim. l 

